Hydrogen is utilized in a wide variety of industries ranging from aerospace to food production to oil and gas production and refining. Hydrogen is used in these industries as a propellant, an atmosphere, a carrier gas, a diluents gas, a fuel component for combustion reactions, a fuel for fuel cells, as well as a reducing agent in numerous chemical reactions and processes. In addition, hydrogen is being considered as an alternative fuel for power generation because it is renewable, abundant, efficient, and unlike other alternatives, produces zero emissions. While there is wide-spread consumption of hydrogen and great potential for even more, a disadvantage which inhibits further increases in hydrogen consumption is the absence of a hydrogen infrastructure to provide widespread generation, storage and distribution.
One way to overcome this difficulty is through the operation of hydrogen energy stations. At hydrogen energy stations, hydrogen generators such as reformers are used to convert hydrocarbons to a hydrogen rich gas stream. Hydrocarbon-based fuels, such as natural gas, LPG, gasoline, and diesel, require conversion processes to be used as fuel sources for most fuel cells. Current art uses multi-step processes combining an initial conversion process with several clean-up processes. The initial process is most often steam reforming (SR), autothermal reforming (ATR), catalytic partial oxidation (CPOX), or non-catalytic partial oxidation (POX), or combinations thereof. The clean-up processes are usually comprised of a combination of desulphurization, high temperature water-gas shift, low temperature water-gas shift, selective CO oxidation, selective CO methanation or combinations thereof. Alternative processes for recovering a purified hydrogen-rich reformate include the use of hydrogen selective membrane reactors and filters. The gaseous hydrogen is then stored in stationary storage vessels at the hydrogen energy stations to provide inventory to fuel hydrogen vehicles.
Currently, gaseous hydrogen is typically dispensed to hydrogen vehicles at a pressure of 350 bar. However, in order to extend the range of hydrogen vehicles, it is desirable to increase the storage density of gaseous hydrogen in hydrogen vehicles. Therefore, it is desirable to dispense gaseous hydrogen to hydrogen vehicles at an increased pressure of 700 bar. This increase in pressure will require cooling of the gaseous hydrogen during dispensing as the temperature of the gaseous hydrogen will increase due to the heat of compression. Conventional heat transfer of this fast flowing stream would require a very large heat exchanger. In addition, the mechanical cooler for this heat exchanger would have to be located remotely from the dispenser or be constructed to meet Class 1, Division 2, Group B electrical code as defined by OSHA regulations.
In addition to increasing the storage density of gaseous hydrogen in hydrogen vehicles, it is also desirable to use cold gaseous hydrogen (“cryocooled”) storage tanks to increase the amount of gaseous hydrogen stored per unit volume versus conventional stationary storage tanks while avoiding the energy penalties associated with hydrogen liquefaction. The cold gaseous hydrogen (“cryocooled”) storage tanks store gaseous hydrogen at a high pressure.
The present invention addresses these challenges by disclosing an apparatus and method for providing a hydrogen rich gas stream at a high pressure for use by hydrogen vehicles or other devices requiring hydrogen rich feed streams.